Is $15,215 to install pella 250 series vinyl windows a fair price?

This quote is for the supply only of Pella 250 Series black vinyl windows for a new construction project. Installation is not included. - Quantity: Approximately 26-30 windows - Exterior Color: Black - Types of Windows: - Awning windows (20”x36”, tempered) - Casement windows (30”x36”, 30”x60”, egress and tempered) - Large double casement windows (60”x60”) - Fixed windows (1 or 2 units) - Features: Most windows are tempered or egress as per code requirements

Replacement of six 30-year-old wood casement windows with Pella Impervia fiberglass units. - Window Type: Casement - Material: Pella Impervia Fiberglass - Number of Windows: 6 - Large Casements: - One window: 98" x 57" (with picture-glass center) - Two windows: 70" x 58" (each with picture-glass center) - Smaller Casements: - Three windows: 46" x 45" (each with two sashes)

This quote is for the replacement of 6 windows with new Pella vinyl windows, including full frame installation and disposal of old windows. The total cost is $9,314, with a $5,000 down payment and the remaining $4,314 to be financed. The quote includes a lifetime labor warranty and a lifetime manufacturer warranty, though the homeowner notes limitations. - Number of Windows: 6 - Window Types: 4 single hung vinyl windows, 2 double hung windows - Grids: 3 single hung windows will have grids, both double hung windows will have grids - Manufacturer: Pella company - Features: Silver coated, foam insulation inside frames, double pane, non-tempered - Installation Type: Full frame installation - Additional Work: Add frame/covering around windows where outside and inside walls meet to prevent rain/water leaks, clean up and dispose of old windows - Window Sizes: 3 windows are 35.5x70.5, 2 windows are 43x35.5, 1 window is 35.5x34.5 - Warranty: Lifetime labor warranty, lifetime manufacturer warranty (transferable, but homeowner notes limitations regarding ownership transfer)